(1) Field of the Invention
The invention relates to a gatherer stitcher having a common drive unit driving at least two operating shafts operating at least one and/or at least two different operating units, where the operating shafts can include in particular a gatherer chain and/or stitching station and/or a feeder and/or a stitching carriage and/or an ejector and/or a 3-cutter. More particularly the invention pertains to an adjusting apparatus having at least one adjustment drive that can be controlled to set a phase angle between the two operating shafts.
(2) Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
Gatherer stitchers are generally paper-processing machines with which a product, for example a brochure, is assembled from a plurality of folded sheets and is stitched. Printed folded sheets from stacks, lying on folded sheet feeders or standing on the spine, are supplied in separated form, opened and placed on a gatherer chain. The number of folded sheets to be stitched is gathered and aligned on the gatherer chain by means of drivers. The gatherer chain transports the gathered folded sheets to a stitching device, where these are stitched with wire staples by means of stitching heads. In order to trim the edge of the stitched products, what is known as a trimmer (3-cutter) is normally provided after the ejector, from which the end products are transported onward to a delivery. If appropriate, perforation of the products can be provided.
In gatherer stitchers, two stitching principles can expediently be employed: stitching at a standstill or stitching on the moving product. In order to perform stitching on the moving product, the stitching device, comprising stitching carriage and bending-over device or stitching station, has to be moved together with the product to be stitched and has to be coordinated with the movement of the latter, at least for some time.
The gatherer stitcher is often driven by a central electric motor. In this case, the various subassemblies, such as the stitching apparatus, the gatherer chain, the folded sheet feeder, the ejector, the trimmer and possibly further components are driven by various gear mechanisms and a common shaft, what is known as a king shaft.
The respective subassembly comprises at least one operating shaft driven by the common shaft in order to fulfill its function, and to some extent there is also a plurality of operating shafts per subassembly. For instance, a folded sheet feeder has three corresponding shafts, in order to pull off the sheet and to open it in order to lay it on the gatherer chain.
Gatherer stitchers are often intended to be able to process an extremely wide range of sheets. For instance, papers of different size and/or different strengths are to be processed. For this purpose, it is to some extent necessary to adjust the phase angle between the operating shafts of different subassemblies and/or between the operating shafts of a subassembly. Hitherto, this has been carried but by hand, which is very time-consuming and to some extent relatively inaccurate.